Proton exchange membrane fuel cell with a movable membrane electrode assembly device

ABSTRACT

The disclosure relates to a proton exchange membrane fuel cell. The fuel cell includes: a container, wherein the container includes a reacting room, a fuel room connected to the reacting room through a fuel inputting hole, a fuel inputting door located on the fuel inputting hole, a waste collecting room connected to the reacting room through a waste outputting hole, a waste outputting door located on the waste outputting hole; a membrane electrode assembly device located in the reacting room, wherein the reacting room is divided into an anode electrode space and a cathode electrode space connected to the outside through a pipe, the volume of the anode electrode space and the cathode electrode space can be changed by moving the membrane electrode assembly device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 15/444,183, filed on Feb. 27, 2017, entitled“PROTON EXCHANGE MEMBRANE FUEL CELL,” which claims all benefits accruingunder 35 U.S.C. § 119 from China Patent Application No. 201610197850.4,filed on Mar. 31, 2016, in the China Intellectual Property Office, thecontents of which are hereby incorporated by reference.

FIELD

The subject matter herein generally relates to fuel cell, andparticularly, to a proton exchange membrane fuel cell.

BACKGROUND

Fuel cells can generally be classified into alkaline, solid oxide, andproton exchange membrane fuel cells. The proton exchange membrane fuelcell has received increasingly more attention and has developed rapidlyin recent years.

Typically, the proton exchange membrane fuel cell includes a number ofseparated fuel cell work units. Each work unit includes a fuel cellmembrane electrode assembly (MEA), flow field plates (FFP), currentcollector plates (CCP). However, the traditional proton exchangemembrane fuel cell also need related support equipment, such as blowers,valves, and pipelines, to input and output the fuel and oxygen gas.Thus, the traditional proton exchange membrane fuel cell has complicatedstructure and relatively high cost.

What is needed, therefore, is to provide a proton exchange membrane fuelcell which can overcome the shortcomings as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the embodiments can be better understood with referenceto the following drawings. The components in the drawings are notnecessarily drawn to scale, the emphasis instead being placed uponclearly illustrating the principles of the embodiments. Moreover, in thedrawings, like reference numerals designate corresponding partsthroughout the several views.

FIG. 1 is a schematic view of one embodiment of a fuel cell.

FIG. 2 is a schematic, cross-sectional view, along a line II-II of FIG.1.

FIG. 3 is a schematic view of one embodiment of a container of a fuelcell.

FIG. 4 is a schematic view of one embodiment of a membrane electrodeassembly device of a fuel cell.

FIG. 5 is a schematic view of another embodiment of a fuel cell.

FIG. 6 is a schematic view of another embodiment of a fuel cell.

FIG. 7 is a schematic view of another embodiment of a fuel cell.

DETAILED DESCRIPTION

It will be appreciated that for simplicity and clarity of illustration,where appropriate, reference numerals have been repeated among thedifferent figures to indicate corresponding or analogous elements. Inaddition, numerous specific details are set forth in order to provide athorough understanding of the embodiments described herein. However, itwill be understood by those of ordinary skill in the art that theembodiments described herein can be practiced without these specificdetails. In other instances, methods, procedures, and components havenot been described in detail so as not to obscure the related relevantfeature being described. The drawings are not necessarily to scale, andthe proportions of certain parts may be exaggerated to be betterillustrate details and features. The description is not to considered aslimiting the scope of the embodiments described herein.

Several definitions that apply throughout this disclosure will now bepresented.

The connection can be such that the objects are permanently connected orreleasably connected. The term “outside” refers to a region that isbeyond the outermost confines of a physical object. The term “inside”indicates that at least a portion of a region is partially containedwithin a boundary formed by the object. The term “substantially” isdefined to essentially conforming to the particular dimension, shape orother word that substantially modifies, such that the component need notbe exact. For example, substantially cylindrical means that the objectresembles a cylinder, but can have one or more deviations from a truecylinder. The term “comprising” means “including, but not necessarilylimited to”; it specifically indicates open-ended inclusion ormembership in a so-described combination, group, series and the like. Itshould be noted that references to “an” or “one” embodiment in thisdisclosure are not necessarily to the same embodiment, and suchreferences mean at least one.

Referring to FIGS. 1 and 2, a proton exchange membrane fuel cell 10 ofone embodiment is provided. The proton exchange membrane fuel cell 10includes a container 12 and a membrane electrode assembly device 14located in the container 12. The membrane electrode assembly device 14includes a gasket ring 146 defining a through hole and a membraneelectrode assembly 140 located on the gasket ring 146 and covering thethrough hole.

The container 12 includes an annular internal wall 120 and an annularexternal wall 121 surrounding the annular internal wall 120. The annularinternal wall 120 and the annular external wall 121 are connected toeach other by a bottom wall 122 and a top wall 123. A reacting room 124is defined by the annular internal wall 120. A storage room 125 isdefined between the annular internal wall 120 and the annular externalwall 121. The storage room 125 is divided into a fuel room 1252 and awaste room 1254. The fuel room 1252 is in communication with thereacting room 124 through a fuel inputting hole 126, and the waste room1254 is in communication with the reacting room 124 through a wasteoutputting hole 128. A fuel inputting door 127 is located on the fuelinputting hole 126, and a waste outputting door 129 is located on thewaste outputting hole 128. A gas exchange hole 1230 is defined on thetop wall 123 and used to communicate the reacting room 124 to theoutside atmosphere. The shape and size of the gas exchange hole 1230 isnot limited.

The annular internal wall 120 and the annular external wall 121 can havea cross-section shape, such as round, ellipse, triangle, square, or anymultilateral shape. The cross section shapes of the annular internalwall 120 and the annular external wall 121 can be the same as shown inFIG. 2 or different as shown in FIG. 3. Referring to FIG. 2, in oneembodiment, the annular internal wall 120 and the annular external wall121 can be substantially cconcentric cylinders spaced from each other.The space between the annular internal wall 120 and the annular externalwall 121 is divided into the fuel room 1252, and the waste room 1254 bytwo plates 1202. Referring to FIG. 3, in one embodiment, the annularinternal wall 120 and the annular external wall 121 can be tangent andin direct contact with each other at two places so that the spacetherebetween is divided into the fuel room 1252 and the waste room 1254.

The fuel inputting door 127 is fixed on the inner surface of thereacting room 124. The fuel inputting door 127 would be closed when thepressure of the reacting room 124 is higher than the pressure of thefuel room 1252, and the fuel inputting door 127 would be open when thereacting room 124 is lower than the pressure of the fuel room 1252. Thewaste outputting door 129 is fixed on the inner surface of the wasteroom 1254. The waste outputting door 129 would be open when the pressureof the reacting room 124 is higher than the pressure of the waste room1254, and the waste outputting door 129 would be closed when thereacting room 124 is lower than the pressure of the waste room 1254. Theshape and size of the container 12 is not limited as long as thecontainer 12 can be divided into the reacting room 124, the fuel room1252 and the waste room 1254. The container 12 can have a plurality offuel rooms 1252 and a plurality of waste rooms 1254.

The membrane electrode assembly device 14 is located in the reactingroom 124 and divides the reacting room 124 into an anode electrode space1242 and a cathode electrode space 1244. The membrane electrode assemblydevice 14 is movable in the reacting room 124 so that the volume of theanode electrode space 1242 and the cathode electrode space 1244 isvariable.

Referring to FIG. 4, in one embodiment, the membrane electrode assembly140 includes a proton exchange membrane 143, an anode electrode 142 anda cathode electrode 141. The proton exchange membrane 143 comprises afirst surface and a second surface opposite to the first surface. Theanode electrode 142 is located on the first surface and in the anodeelectrode space 1242, and the cathode electrode 141 is located on thesecond surface and in the cathode electrode space 1244. Alternatively,the membrane electrode assembly 140 can also include an anode currentcollector 145 located on the anode electrode 142 and a cathode currentcollector 144 located on the cathode electrode 141.

The material of the proton exchange membrane 143 can beperfluorosulfonic acid, polystyrene sulfonic acid, polystyrenetrifluoroacetic acid, phenol formaldehyde resin acid, or hydrocarbons.In one embodiment, both the anode electrode 142 and the cathodeelectrode 141 includes a gas diffusion layer and catalyst layer locatedon the gas diffusion layer to form a double layer structure. In oneembodiment, both the anode electrode 142 and the cathode electrode 141includes a gas diffusion layer and a catalyst material dispersed in thegas diffusion layer to form a single layer composite. The gas diffusionlayer can be a carbon nanotube layer or a carbon fiber layer. Thecatalyst material of the cathode electrode 141 can be noble metalparticles, such as platinum particles, gold particles or rutheniumparticles. The catalyst material of the anode electrode 142 can beselected according to the fuel. When the fuel is biofuel, such asglucose, the catalyst material of the anode electrode 142 is biofuelcatalyst, such as glucose oxidase. When the fuel is ether, the catalystmaterial of the anode electrode 142 is a noble metal. The cathodecurrent collector 144 and the anode current collector 145 are metal meshor metal layer having through holes and used to collect electrons orprotons. Furthermore, the cathode current collector 144 and the anodecurrent collector 145 can protect the entire membrane electrode assembly140 during the membrane electrode assembly 140 moving.

In one embodiment, the proton exchange membrane 143 is aperfluorosulfonic acid film. The cathode electrode 141 includes a firstcarbon nanotube layer and platinum particles dispersed in the firstcarbon nanotube layer. The size of the platinum particles is in a rangefrom about 1 nanometer to abut 10 nanometers. The distribution of theplatinum particles is less than 0.5 mg/cm² (milligram per squarecentimeter). The anode electrode 142 includes a second carbon nanotubelayer and enzymatic catalyst or microbe dispersed in the second carbonnanotube layer. The enzymatic catalyst can be oxidase or dehydrogenase.The enzymatic catalyst is dispersed on the surface of the carbonnanotubes of the carbon nanotube layer. The carbon nanotubes of thecarbon nanotube structure include a plurality of carboxyls or hydroxyls.The enzymatic catalyst is attached to the surface of the carbonnanotubes via the carboxyls or hydroxyls thereof. Both the cathodecurrent collector 144 and the anode current collector 145 are coppermesh.

The gasket ring 146 is used to support the membrane electrode assembly140 and seal the gaps between the annular internal wall 120 and themembrane electrode assembly 140. The gasket ring 146 includes an annularbody 1460, a cathode connector 1464 located on the annular body 1460,and an anode connector 1466 located on the annular body 1460. Theannular body 1460 and the reacting room 124 have the same cross sectionshapes and size. The outer side surface of the annular body 1460 is indirect contact with the inner side surface of the reacting room 124. Theannular body 1460 defines an annular groove 1462 on the inner surface ofthe annular body 1460 so that the membrane electrode assembly 140 can bepartially embedded in the annular groove 1462. The thickness and size ofthe gasket ring 146 can be selected according to need. The material ofthe gasket ring 146 can be a polymer, such as rubber.

The cathode connector 1464 is electrically connected to the cathodeelectrode 141, and the anode connector 1466 is electrically connected tothe anode electrode 142. In one embodiment, the cathode connector 1464is electrically connected to the cathode electrode 141 via the cathodecurrent collector 144, and the anode connector 1466 is electricallyconnected to the anode electrode 142 through the anode current collector145. The cathode connector 1464 and the anode connector 1466 arepartially exposed to the cathode electrode space 1244 and can beelectrically connected to a load 16 by wires 18.

In one embodiment, both the cathode connector 1464 and the anodeconnector 1466 are a metal layer. The annular groove 1462 comprises atop inner surface and a bottom inner surface. The cathode connector 1464is located on the top outer surface of the annular body 1460 and extendto the top inner surface of the annular groove 1462 to in direct contactwith the cathode current collector 144. The anode connector 1466 islocated on the top outer surface of the annular body 1460 and extend tothe bottom inner surface of the annular groove 1462 to in direct contactwith the anode current collector 145. The anode connector 1466 should beinsulated from the cathode current collector 144 and the cathodeelectrode 141 by an insulating layer.

In working process of the proton exchange membrane fuel cell 10, thecathode connector 1464 and the anode connector 1466 are electricallyconnected to the load 16 via two wires 18. When the membrane electrodeassembly device 14 moves toward the top wall 123, the volume of theanode electrode space 1242 increases, and pressure of the anodeelectrode space 1242 decrease. The fuel inputting door 127 would beopen, and the outputting door 129 would be closed. The glucose biofuelenters the anode electrode space 1242 from the fuel room 1252. At thesame time, the waste gas of the cathode electrode space 1244 isexhausted through the gas exchange hole 1230 because the pressure of thecathode electrode space 1244 increase. When the membrane electrodeassembly device 14 moves toward the bottom wall 122, the volume of theanode electrode space 1242 decreases, and pressure of the anodeelectrode space 1242 increase. The fuel inputting door 127 would beclosed, and the outputting door 129 would be open. The waste biofuelenters the waste room 1254 from the anode electrode space 1242. At thesame time, the air outside of the reacting room 124 enters the cathodeelectrode space 1244 through the gas exchange hole 1230 because thepressure of the cathode electrode space 1244 decrease.

On the side of the anode electrode 142, the glucose biofuel is appliedand decomposed by the enzymatic catalyst to form electrons and protons(H). The protons are transferred from the anode electrode 142 to thecathode electrode 141 by the proton exchange membrane 143. At the sametime, the electrons arrive at the cathode electrode 141 by the externalelectrical circuit. On the side of the cathode electrode 141, oxygen isapplied and reacts with the protons and electrons as shown in thefollowing equation: 1/2O₂+2H++2e→H₂O. In the process, a potentialdifference is generated, and a current flows through the load 16.

Because the fuel and oxygen gas are input and output by moving themembrane electrode assembly device 14, the proton exchange membrane fuelcell 10 does not need the support equipment, such as blowers, valves,and pipelines. The moving direction of the membrane electrode assemblydevice 14 can be vertical or horizontal. In one embodiment, the anglebetween the moving direction of the membrane electrode assembly device14 and the horizontal plane can be less than 90 degrees, such as in arange from about 30 degrees to about 60 degrees. Thus, the waterresulted from the reaction can be easy output through the.

Referring to FIG. 5, a proton exchange membrane fuel cell 10A of anotherembodiment is provided. The proton exchange membrane fuel cell 10Aincludes the container 12 and the membrane electrode assembly device 14located in the container 12. The membrane electrode assembly device 14includes a gasket ring 146 defining a through hole and a membraneelectrode assembly 140 located on the gasket ring 146 and covering thethrough hole.

The proton exchange membrane fuel cell 10A is similar to the protonexchange membrane fuel cell 10 above except that the proton exchangemembrane fuel cell 10A further includes an oxygen room 130, the oxygenroom 130 is in communication with the cathode electrode space 1244through a gas inputting hole 132, and a gas inputting door 134 islocated on the gas inputting hole 132. The gas inputting door 134 fixedon the inner surface of the cathode electrode space 1244. The oxygenroom 130 is above the cathode electrode space 1244, and the gasinputting hole 132 is formed on the top wall 123.

The gas inputting door 134 would be closed when the pressure of thecathode electrode space 1244 is higher than the pressure of the oxygenroom 130, and the gas inputting door 134 would be open when the pressureof the cathode electrode space 1244 is lower than the pressure of theoxygen room 130. A gas outputting door 1232 is located on the gasexchange hole 1230 so that the gas exchange hole 1230 is only used toexhaust waste gas. The gas outputting door 1232 is fixed on the outersurface of the top wall 123. The gas outputting door 1232 would be openwhen the pressure of the cathode electrode space 1244 is higher than thepressure of the atmosphere, and the gas outputting door 1232 would beclosed when the pressure of the cathode electrode space 1244 is lowerthan the pressure of the atmosphere.

Referring to FIG. 6, a proton exchange membrane fuel cell 10B of anotherembodiment is provided. The proton exchange membrane fuel cell 10Bincludes the container 12 and the membrane electrode assembly device 14located in the container 12. The membrane electrode assembly device 14includes a gasket ring 146 defining a through hole and a membraneelectrode assembly 140 located on the gasket ring 146 and covering thethrough hole.

The proton exchange membrane fuel cell 10B is similar as the protonexchange membrane fuel cell 10 above except that the moving direction ofthe membrane electrode assembly device 14 is horizontal. The fuel room1252 is above the reacting room 124 and the fuel inputting hole 126 islocated at a common wall of the fuel room 1252 and the anode electrodespace 1242. The bottom wall of the fuel room 1252 is also the top wallof the reacting room 124. The waste room 1254 is adjacent to andcommunicated to the anode electrode space 1242 and under the fuel room1252. The fuel in the fuel room 1252 is ethanol gas. The catalyst of theanode electrode 142 is noble metal particles. The gas exchange hole 1230is located at the bottom corner of the cathode electrode space 1244.Because the membrane electrode assembly 140 is vertical, the waterresulted from the reaction could flow out of the cathode electrode space1244 from the gas exchange hole 1230.

Referring to FIG. 7, a proton exchange membrane fuel cell 10C of anotherembodiment is provided. The proton exchange membrane fuel cell 10C issimilar as the proton exchange membrane fuel cell 10B above except thatthe proton exchange membrane fuel cell 10C further includes a wastewater collecting room 1253 under the reacting room 124. The waste watercollecting room 1253 is communicated to the cathode electrode space 1244through a waste water outputting hole 1231 at the bottom corner of thecathode electrode space 1244. The gas exchange hole 1230 is spaced fromthe waste water outputting hole 1231.

The embodiments shown and described above are only examples. Even thoughnumerous characteristics and advantages of the present technology havebeen set forth in the forego description, together with details of thestructure and function of the present disclosure, the disclosure isillustrative only, and changes may be made in the detail, including inmatters of shape, size and arrangement of the parts within theprinciples of the present disclosure up to, and including, the fullextent established by the broad general meaning of the terms used in theclaims.

Depending on the embodiment, certain of the steps of methods describedmay be removed, others may be added, and the sequence of steps may bealtered. The description and the claims drawn to a method may includesome indication in reference to certain steps. However, the indicationused is only to be viewed for identification purposes and not as asuggestion as to an order for the steps.

What is claimed is:
 1. A proton exchange membrane fuel cell, comprising:a container, wherein the container comprise: an annular internal wall,wherein a reacting room is defined by the annular internal wall; anannular external wall surrounding the annular internal wall, wherein astorage room is defined between the annular internal wall and theannular external wall and divided into a fuel room and a waste room, thefuel room is in communication with the reacting room through a fuelinputting hole, and the waste room is in communication with the reactingroom through a waste outputting hole; a bottom wall connecting theannular internal wall and the annular external wall; a top wallconnecting the annular internal wall and the annular external wall,wherein a gas exchange hole is defined on the top wall; a fuel inputtingdoor located on the fuel inputting hole; and a waste outputting doorlocated on the waste outputting hole; and a membrane electrode assemblydevice located in the reacting room and dividing the reacting room intoa first electrode space and a second electrode space, wherein themembrane electrode assembly device is movable in the reacting room sothat volumes of the first electrode space and the second electrode spaceis variable, and the second electrode space is in communication with anoutside atmosphere through the gas exchange hole.
 2. The proton exchangemembrane fuel cell of claim 1, wherein the membrane electrode assemblydevice comprises a gasket ring defining a through hole and a membraneelectrode assembly located on the gasket ring and covering the throughhole.
 3. The proton exchange membrane fuel cell of claim 2, wherein themembrane electrode assembly comprises an anode current collector, ananode electrode, a proton exchange membrane, a cathode electrode, and acathode current collector.
 4. The proton exchange membrane fuel cell ofclaim 3, wherein the gasket ring comprises an annular body, a cathodeconnector located on the annular body, and an anode connector located onthe annular body.
 5. The proton exchange membrane fuel cell of claim 4,wherein the anode connector is electrically connected to the anodeelectrode, and the cathode connector is electrically connected to thecathode electrode.
 6. The proton exchange membrane fuel cell of claim 5,wherein the anode connector and the cathode connector are partiallyexposed to the second electrode space.
 7. The proton exchange membranefuel cell of claim 4, wherein the annular body defines an annular grooveon an inner surface of the annular body and the membrane electrodeassembly is partially embed in the annular groove.
 8. The protonexchange membrane fuel cell of claim 1, wherein when the membraneelectrode assembly device moves toward the gas exchange hole, the volumeof the first electrode space increases and the volume of the secondelectrode space decreases, a pressure of the first electrode spacedecrease and a pressure of the second electrode space increase, the fuelinputting door is open and the outputting door is closed so that fuelenters the first electrode space from the fuel room, and waste gas ofthe second electrode space is exhausted through the gas exchange hole;and when the membrane electrode assembly device moves away from the gasexchange hole, the volume of the first electrode space decreases and thevolume of the second electrode space increases, the pressure of thefirst electrode space increase and the pressure of the second electrodespace decrease, the fuel inputting door is closed and the outputtingdoor is open so that waste fuel enters the waste room from the firstelectrode space, and the air outside of the reacting room enters thesecond electrode space through the gas exchange hole.
 9. The protonexchange membrane fuel cell of claim 8, wherein the fuel inputting dooris fixed on the inner surface of the reacting room, the fuel inputtingdoor is closed when the pressure of the first electrode space is higherthan the pressure of the fuel room, and the fuel inputting door is openwhen the pressure of the first electrode space is lower than thepressure of the fuel room; and the waste outputting door is fixed on theinner surface of the waste room, the waste outputting door is open whenthe pressure of the first electrode space is higher than the pressure ofthe waste room, and the waste outputting door is closed when thepressure of the first electrode space is lower than the pressure of thewaste room.
 10. The proton exchange membrane fuel cell of claim 1,further comprising: an oxygen room in communication with the secondelectrode space through a gas inputting hole; a gas inputting doorlocated on the gas inputting hole; and a gas outputting door located onthe gas exchange hole; wherein when the membrane electrode assemblydevice moves toward the gas exchange hole, the volume of the firstelectrode space increases and the volume of the second electrode spacedecreases, a pressure of the first electrode space decrease and apressure of the second electrode space increase, the fuel inputting dooris open and the outputting door is closed so that fuel enters the firstelectrode space from the fuel room, and the gas inputting door is closedand the gas outputting door is open so that waste gas of the secondelectrode space is exhausted through the gas outputting door; and whenthe membrane electrode assembly device moves away from the gas exchangehole, the volume of the first electrode space decreases and the volumeof the second electrode space increases, the pressure of the firstelectrode space increase and the pressure of the second electrode spacedecrease, the fuel inputting door is closed and the outputting door isopen so that waste fuel enters the waste room from the first electrodespace, and the gas outputting door is closed and the gas inputting dooris open so that oxygen gas enters the second electrode space through thegas inputting door.
 11. The proton exchange membrane fuel cell of claim10, wherein the fuel inputting door is fixed on the inner surface of thereacting room, the fuel inputting door is closed when the pressure ofthe first electrode space is higher than the pressure of the fuel room,and the fuel inputting door is open when the pressure of the firstelectrode space is lower than the pressure of the fuel room; the wasteoutputting door is fixed on the inner surface of the waste room, thewaste outputting door is open when the pressure of the first electrodespace is higher than the pressure of the waste room, and the wasteoutputting door is closed when the pressure of the first electrode spaceis lower than the pressure of the waste room; the gas inputting door isfixed on the inner surface of the second electrode space, the gasinputting door is closed when the pressure of the second electrode spaceis higher than the pressure of the oxygen room, and the gas inputtingdoor is open when the pressure of the second electrode space is lowerthan the pressure of the oxygen room; and the gas outputting door isfixed on the outer surface of the second electrode space, the gasoutputting door is open when the pressure of the second electrode spaceis higher than the pressure of the atmosphere, and the gas outputtingdoor is closed when the pressure of the second electrode space is lowerthan the pressure of the atmosphere.
 12. The proton exchange membranefuel cell of claim 1, wherein the fuel room is above the reacting roomand the fuel inputting hole is located at a common wall of the fuel roomand the first electrode space, and the waste room is adjacent to andcommunicated to the first electrode space and under the fuel room. 13.The proton exchange membrane fuel cell of claim 12, wherein the membraneelectrode assembly is vertical and moveable along the horizontaldirection, and the gas exchange hole is located at the bottom corner ofthe second electrode space so that water caused in the second electrodespace flow out of the second electrode space from the gas exchange hole.14. The proton exchange membrane fuel cell of claim 12, furthercomprising a waste water collecting room under the reacting room andcommunicated to the second electrode space through a waste wateroutputting hole at the bottom corner of the second electrode space; andthe gas exchange hole is spaced from the waste water outputting hole.